Determination of the Neutron-Capture Rate of 17C for the R-process Nucleosynthesis
nucl-ex
/ Authors
M. Heine, S. Typel, M. -R. Wu, T. Adachi, Y. Aksyutina, J. Alcantara, S. Altstadt, H. Alvarez-Pol, N. Ashwood, T. Aumann
and 117 more authors
V. Avdeichikov, M. Barr, S. Beceiro-Novo, D. Bemmerer, J. Benlliure, C. A. Bertulani, K. Boretzky, M. J. G. Borge, G. Burgunder, M. Caamano, C. Caesar, E. Casarejos, W. Catford, J. Cederkäll, S. Chakraborty, M. Chartier, L. V. Chulkov, D. Cortina-Gil, R. Crespo, U. Datta Pramanik, P. Diaz Fernandez, I. Dillmann, Z. Elekes
/ Abstract
With the R$^{3}$B-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of $^{18}$C at a projectile energy around 425~AMeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of $^{17}$C into the ground state of $^{18}$C. Those data have been used to constrain theoretical calculations for transitions populating excited states in $^{18}$C. This allowed to derive the astrophysical cross section $σ^{*}_{\mathrm{n}γ}$ accounting for the thermal population of $^{17}$C target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures $T_{9}\leq{}1$~GK. Network simulations with updated neutron-capture rates and hydrodynamics according to the neutrino-driven wind model as well as the neutron-star merger scenario reveal no pronounced influence of neutron capture of $^{17}$C on the production of second- and third-peak elements in contrast to earlier sensitivity studies.